Short Message Service (SMS) is an inherent capability of most digital wireless telecommunications systems. The radio technologies associated with each of the digital wireless telecommunications systems are technically incompatible at the radio signal layer, but most are compatible at the intersystem SS7 transport layer. Currently, the differing RF technologies, e.g., time division multiple access (TDMA), code division multiple access (CDMA), and global system for mobile telecommunications (GSM), have at least partial technical compatibility over the telephone industry's SS7 inter-networking system. The partial compatibility of these RF technologies is possible because the basic transport format is specified in the SS7 standard; however, many of the messaging details are implementation specific.
Even though it is possible for current short message service center platforms (SMSC) to support all of these multiple protocols, typically, an installed SMSC only supports the protocol of the cellular telecommunication system into which it is installed. For example, if the SMSC is installed into an IS136 type TDMA system, the SMSC supports only the TDMA protocol. Similarly, if the SMSC is installed into a GSM system, then the SMSC supports only the GSM protocol. In other words, although most current SMSC's can interface with any of the currently popular digital cellular systems, the SMSC's do so on an individual basis, not all simultaneously.
For example, in one network, the nodes communicate using different data formatting standards, such as integrated services digital network (ISDN) and the Japanese X.50 standard. Each of the nodes is connected to a format converter. The format converter acts as a bi-directional converter for converting between two data formats and thus allows communication between the two nodes.
The format converter reformats the data formatted in the X.50 standard into the ISDN format. The format converter accomplishes the conversion by storing the incoming X.50 data in an aligned data RAM with offsets, to provide an appropriate alignment among the frames of the data. Then, a format conversion module reformats the data into the ISDN format one byte at a time.
In another network, a subscriber in an electronic messaging network can access messages in a variety of formats. A subscriber may receive messages through a variety of types of equipment, such as a voice mail system, an e-mail system, a facsimile machine and a telephone, all connected to a wireline network. The subscriber may access these messages through a pager, a cellular telephone, or a personal digital assistant, each connected to a different wireless network. The subscriber selects the wireline or wireless network and media format to be used for delivering messages or notifying a subscriber that a message has been received.
For example, the subscriber may elect to have notification of a voice mail or facsimile receipt directed to the personal digital assistant (PDA) in the form of an e-mail message. In accordance with the method of the network, the subscriber's selection is implemented through the personal intercommunications inter-networking system, which performs the appropriate data conversion from one protocol to another and delivers the e-mail message.
In yet another network, an intelligent signaling transfer point (ISTP) is included in a telephone network with a database for storing call processing control information. Calls from one station on the network to another are either passed through or intercepted at the ISTP and screened in accordance with criteria stored in the database, such as time of day, a certain originating area or caller, or a specified call count value.
In still another network, a data collection device is provided for use with any one of the following: TDMA; CDMA; frequency division multiple access (FDMA); GSM; and personal access communications systems (PACS) technologies. But, the data collection device does not use multiple such technologies in a single system. These systems and methods only teach conversion between two specific formats.
A further limitation with conventional SMS systems is that the SMS data transmissions are handled by the SMSC. The SMSCs use the address information contained within the data transmission to communicate with Home Location Registers (“HLRs”) and route the data to the correct recipient. The SMS text messages can originate and terminate at cellular mobile radiotelephones or at other external messaging entities coupled to the cellular network such as email, voicemail, and web-based messaging systems.
SMS data transmissions are routed from the SMSC to the recipient via one or more switches. Once an SMS data packet arrives at the receiving device, the message is extracted from its packet and formatted for delivery. For example, if the receiving unit is a cellular mobile radiotelephone, the unit formats the message for display on the unit's display screen. Alternatively, if the receiving unit is an external messaging system, an SMSC can format the message for transmission within an email message for delivery to a user external to the cellular telephone system.
The SMSCs are deployed by cellular carriers and serve the customers within the carrier's private network. For example, FIGS. 5 and 6 illustrate conventional SMS systems 500 and 600 using SMSCs operated by a local and regional carrier, respectively. In each of the conventional systems illustrated in FIGS. 5 and 6, the SMSCs 525 and 625 receive and store messages from radios 505 and 605. The SMSCs determine the destinations for the messages through a set of queries. Once there is available bandwidth, the SMSC can deliver the messages to the appropriate destination. SMSCs 525 and 625 can also receive messages from external systems, such as an email system, that are destined for radios 505 and 605. The SMSCs 525 and 625 query the HLRs 520 and 620 to determine the locations of the destination radios 505 and 605. Once there is available bandwidth, the SMSCs 525 and 625 can deliver the messages to radios 505 and 605. Significantly, all messages transmitted within each of systems 500 and 600 must use the same communication protocol. Conventional SMSCs 525 and 625 generally are not equipped to convert messages having different communication protocols.
FIGS. 7 and 8 illustrate conventional systems 700 and 800 for communicating roaming messages between different networks. FIG. 7 illustrates a home SMSC 730 coupled to HLR 735 that transmits messages to and receives messages from switch 715. FIG. 8 illustrates system 800 where a local SMSC 825 and an SMS clearinghouse 830 are used to communicate with a home SMSC 835. In each of systems 700 and 800, the switch or the SMSCs send a set of queries to the destination network in order to transmit messages. Furthermore, although the roaming messages are transmitted between different networks, the format of the messages is the same.
The SMSC of the conventional networks illustrated in FIGS. 5, 6, 7, and 8 acts as a “store and forward” system for the SMS data transmissions. The SMSC determines the routing for the data transmission and places the data in a queue for delivery to a cellular mobile radiotelephone or other messaging device. One shortcoming of conventional SMS systems is the delay in delivering the data transmissions queued at the SMSC. Typical delays for delivering messages can last minutes or hours.
One of the causes for the delay is that SMS messages are often assigned a lower delivery priority as compared to data transmissions containing voice communications. The low priority assigned to SMS messages stored in a queue at the SMSC causes a delay in their delivery. This delay is particularly noticeable when a carrier lacks sufficient bandwidth on its network. A further cause for delay are the inefficient steps an SMSC takes to route and deliver a data transmission. For example, the SMSC queries the HLR each time it is delivering a message to a mobile communication device. The HLR is a database of profiles for subscribers comprising account and service information.
Accordingly, there is a need in the art for a system that can efficiently route SMS messages from originators to recipients. Specifically, there is a need in the art to communicate more efficiently with serving switches and avoid the delays caused by an SMSC. A communication platform is needed that delivers messages promptly instead of storing them for later delivery when there is available bandwidth. The needed communication platform should also eliminate unnecessary steps as part of the communication process. There is a further need for a communication platform that can communicate with remote stations that use different digital cellular or personal communication formats.